Hitherto, various fluorine-containing polymer compounds are proposed. The fluorine-containing polymer compounds have the advantageous effects of having properties excellent in heat resistance, oxidation resistance, weather resistance and the like. The fluorine-containing polymer compounds are used as, for example, a water- and oil-repellent agent and a soil release agent by utilizing the properties that the fluorine-containing polymer compounds have low free energy, i.e., difficulty in adherence.
Recently, with respect to compounds containing a Rf group having 8 carbon atoms prepared by telomerization,
Federal Register (FR Vol. 68, No. 73/Apr. 16, 2003 [FRL-7303-8]) (http://www.epa.gov/opptintr/pfoa/pfoafr.pdf),
EPA Environmental News for release Monday Apr. 14, 2003 “EPA INTENSIFIES SCIENTIFIC INVESTIGATION OF A CHEMICAL PROCESSING AID” (http://www.epa.gov/opptintr/pfoa/pfoaprs.pdf), and
EPA OPPT FACT SHEET Apr. 14, 2003 (http://www.epa.gov/opptintr/pfoa/pfoafacts.pdf)
announced that a “telomer” may possibly metabolize or decompose to perfluorooctanoic acid (hereinafter abbreviated as “PFOA”).
EPA (Environmental Protection Agency of USA) has announced that the EPA intensifies the scientific investigation on PFOA (cf. EPA Report “PRELIMINARY RISK ASSESSMENT OF THE DEVELOPMENTAL TOXICITY ASSOCIATED WITH EXPOSURE TO PERFLUOROOCTANOIC ACID AND ITS SALTS” (http://www.epa.gov/opptintr/pfoa/pfoara.pdf)).
Patent Document 1 (U.S. Pat. No. 4,366,299) discloses a fluorine-containing polymer, but the polymer is not dispersed in water. Patent Document 4 (U.S. Pat. No. 4,127,711) discloses a fluorine-containing polymer which is dispersed in water. Patent Document 5 (U.S. Pat. No. 5,247,008) discloses a fluorine-containing polymer comprising a fluorine-containing monomer, a nitrogen-containing monomer and an alkylene oxide group-containing monomer. In technologies of Patent Documents 1, 4 and 5, the number of carbon atoms in the Rf group of the fluorine-containing monomer is generally at least 8. A fluorine-containing monomer having the Rf group containing 1 to 6 carbon atoms is not sufficiently utilized in industry.
Patent Document 3 (International publication WO2005/090423) discloses that a copolymer, which is based on a fluorine monomer: CH2═CH—C(═O)—O—(CH2)2—(CF2)nF wherein the number of carbon atoms (n) of the Rf group is 1 to 6, and an amino-monomer and a polyethylene glycol monomer as comonomers, is used as soil release agent of the paper use is disclosed, but the specification, including Examples, is silent on a monomer having a vinyl pyrrolidone skeleton.
Patent Document 2 (International publication WO2003/106519) discloses a copolymer, which is based on a fluorine monomer of CH2═CH—C(═O)—O—(CH2)2—(CF2)nF wherein the number (n) of carbon atoms of the Rf group is 4, and an amino-monomer and a pyrrolidone monomer as comonomers, but Examples thereof do not describe the fluorine monomers wherein number (n) of carbon atoms in the Rf group is 6.
Hitherto, a copolymer, which is based on a fluorine monomer CH2═CH—C(═O)—O—(CH2)2—(CF2)nF wherein the number of carbon atoms (n) in the Rf group is 1 to 6, and an amino-monomer and a pyrrolidone monomer as comonomers, has not been described nor suggested.
The fluorine-containing polymers described in these Patent Documents cannot impart enough oil-resistance and water-repellency.
Patent Document 1: U.S. Pat. No. 4,366,299
Patent Document 2: International publication WO2003/106519
Patent Document 3: International publication WO2005/090423
Patent Document 4: U.S. Pat. No. 4,127,711
Patent Document 5: U.S. Pat. No. 5,247,008